The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 18, 1996
Filed:
May. 09, 1994
Applicant:
Inventor:
Tyman H Fikse, La Conner, WA (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21C / ; E21D / ;
U.S. Cl.
CPC ...
299 31 ; 299 33 ; 405142 ;
Abstract
The anchor shoes of a tunnel-boring machine arranged in a circular configuration are individually truncated by being tapered rearwardly so that the girth of the circular anchor shoe configuration can decrease progressively in order to accommodate convergence of superincumbent ground pressure. Preferably the anchor shoes are mounted for tilting of their aft portions to enable the degree of convergence or constriction to be altered. Chordal jacks connecting adjacent anchor shoes exert pressure on them resisting inward swinging of the aft portions of the anchor shoes resulting from superincumbent ground pressure.